# Webbed Moos

"Dr. John Zarkov" (zarkov@lanning.org)
Tue, 21 May 1996 01:49:39 PDT

- Messages sorted by:[ date ][ thread ][ subject ][ author ]

    We are in the process of bringing up a site for research in k-12 distance
    learning which makes heavy use of hybrid (text and graphics) moo-based
    environments. The site will not be open for a little while yet, and may be
    more of interest to the k-12 distance-learning community than to this
    group, but a few comments on the technical side of what we're doing may be
    appropriate here.

    First, our philosophy, for obvious reasons of expense and installation, is
    that we must expect no special clients on the user's end; everything
    special must be done at the server. We assume only Netscape extensions and
    a telnet application accessible through the browser. This seems to be an
    accurate assumption for at least 90% of user sites, and will likely be
    100% soon. Second, the system must run economically at any site, either
    locally on the school's machine, or over the net at a remote provider.

    Under this constraint, we have found that it is quite possible to do the
    following things:

    1. Accept a connection from a browser and open a second window for them
    with a secure TF client running in it.

    2. Employ the text window for ordinary text-based virtual environments
    while simultaneously showing graphics (or other text) in the browser
    window. (You can do both in a single browser window as well, but that
    may be less flexible.)

    3. Update the graphics window on-demand of the server, including writing
    text line-at-a-time if desired into their graphics window. This can be done
    in synchrony for a group of users (such as a class) or on an individual
    basis. Any number of such potentially multi-user graphics channels may
    be supported.

    4. For none of this is it required that the user click on anything or take
    any action to change their browser screen. This means that the grpahics
    window can be updated on-demand by a lecturer in the manner of putting up
    slides, or on-demand by the moo itself as for example when a new location
    is entered.

    5. The content of the graphics window can be taken from any URL in the
    world or from local image caches, or generated on-the-fly by the moo
    server.

    All of this is quite possible without Java, without special clients on the
    user side, and using only a server that can be run on a local school
    system's machine as well as over the net at a remote machine. We can run
    it on a Linux box. In our opinion, some of the approaches being taken
    therefore represent considerable overkill, while others still have the
    (for us) undesirable property of requiring the user to click on things to
    update the screen.

    When the site is ready for visitors, we will allow demo logins, and anyone
    interested will be welcome to come and play with it. I'll post a notice
    here when it's ready. Anyone interested in the distance-learning applications
    is invited to correspond with Sybil Lanning (lanning@lanning.org)

    Best,

    John